Abstract

Sweet potato ( Ipomoea batatas [L.] Lam., cv. Georgia Jet) plants were grown at different C0 2 concentrations (350, 675 and 1000/ μmol mol −1) in controlled environment conditions. The effect of C0 2 enrichment on carbohydrate concentrations in leaves, stems, roots and tubers at different stages of growth and development were investigated. The glucose, sucrose and starch concentrations in leaves increased during 0–35 days after planting as compared to stems and roots receiving increased CO 2 concentrations. However, starch and glucose concentrations increased significantly in tubers during the 50–65 day interval which corresponded with rapid growth of tubers at high CO 2 concentrations. Increasing C0 2 concentrations did not raise the protein content of leaves, roots or tubers at any stages of growth and development. CO 2 enrichment increased the soluble protein concentration in stems during the 20–50 day growth interval which subsequently decreased at maturity.